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Related Concept Videos

Hypoglycemia and Glucagon01:15

Hypoglycemia and Glucagon

Without prolonged fasting, healthy individuals maintain blood glucose levels above 3.5 mM due to a well-adapted neuroendocrine counterregulatory system that effectively prevents acute hypoglycemia, a potentially life-threatening condition. The primary clinical scenarios for hypoglycemia encompass diabetes treatment, inappropriate production of endogenous insulin or insulin-like substances by tumors, and the use of glucose-lowering agents in non-diabetic individuals. Notably, hypoglycemia in the...
Hypoglycemia01:26

Hypoglycemia

Hypoglycemia is a blood glucose level below 70 mg/dL. It commonly occurs in individuals using insulin or insulin-secreting drugs, but may also arise in non-diabetic conditions. People with type 1 diabetes are at the highest risk because they depend on exogenous insulin. People with type 2 diabetes are also at risk, especially when treated with insulin or medications such as sulfonylureas, which increase insulin release regardless of blood glucose levels. It develops when insulin levels exceed...
Hyperglycemia01:29

Hyperglycemia

Hyperglycemia is an abnormally high blood glucose level. It is diagnosed by fasting glucose ≥126 mg/dL, 2-hour oral glucose tolerance test (or OGTT) ≥200 mg/dL, random glucose ≥200 mg/dL with symptoms, or HbA1c ≥6.5%. However, HbA1c results may be unreliable in certain conditions, such as anemia or hemoglobinopathies, and the diagnosis should be confirmed unless classic symptoms are present. Postprandial hyperglycemia is typically considered significant when glucose levels exceed 180 mg/dL two...
Type I Diabetes III: Clinical Manifestations01:19

Type I Diabetes III: Clinical Manifestations

Type 1 diabetes mellitus typically presents with rapid-onset symptoms due to the body’s inability to utilize glucose in the absence of insulin. Since insulin is required for glucose uptake into cells, its deficiency leads to hyperglycemia and cellular energy deprivation, resulting in characteristic clinical features.Polyuria and PolydipsiaOne of the earliest, most prominent symptoms is polyuria (excessive urination). When blood glucose concentrations rise above the renal threshold, the kidneys...
Type II Diabetes Mellitus III: Clinical Manifestations and Diagnosis01:25

Type II Diabetes Mellitus III: Clinical Manifestations and Diagnosis

Type 2 diabetes mellitus develops gradually and is often asymptomatic in early stages.Clinical ManifestationsWhen symptoms appear, they include fatigue, blurred vision, pruritus, delayed wound healing, and recurrent infections, particularly candidal infections. Peripheral neuropathy may present as numbness or tingling in the extremities. Classic hyperglycemia symptoms—polyuria, polydipsia, and polyphagia—are less common. Most patients are overweight and frequently have associated hypertension...
Diabetes: Symptoms, Diagnosis, and Complications01:15

Diabetes: Symptoms, Diagnosis, and Complications

For most patients, experiencing several weeks of polyuria, polydipsia, fatigue, and significant weight loss may indicate the presence of diabetes. Furthermore, adults displaying the phenotypic appearance of type 2 diabetes (particularly those who are obese and not initially insulin-requiring), may have islet cell autoantibodies, suggesting autoimmune-mediated β cell destruction and a diagnosis of latent autoimmune diabetes of adults (LADA). The categorization of glucose homeostasis is based on...

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Randomized Controlled Trial to Study the Acute Effects of Strength Exercise on Insulin Sensitivity in Obese Adults
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Abrupt decrease in serum testosterone levels after an oral glucose load in men: implications for screening for

Lisa M Caronia1, Andrew A Dwyer, Douglas Hayden

  • 1Reproductive Endocrine Unit of the Department of Medicine, Massachusetts General Hospital, Boston, MA, USA.

Clinical Endocrinology
|July 19, 2012
PubMed
Summary
This summary is machine-generated.

Glucose intake significantly lowers testosterone (T) levels in men, regardless of glucose tolerance. This T reduction may stem from testicular issues, with potential central influences, suggesting retesting in a fasting state.

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Improving Strength, Power, Muscle Aerobic Capacity, and Glucose Tolerance through Short-term Progressive Strength Training Among Elderly People
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Characterization of Metabolic Status in Nonhuman Primates with the Intravenous Glucose Tolerance Test
06:59

Characterization of Metabolic Status in Nonhuman Primates with the Intravenous Glucose Tolerance Test

Published on: November 13, 2016

Area of Science:

  • Endocrinology
  • Metabolic Health
  • Men's Health

Background:

  • Serum testosterone (T) levels are crucial for male health.
  • Glucose tolerance (GT) can influence various physiological parameters.
  • The impact of glucose load on T levels across different GT statuses is not fully understood.

Purpose of the Study:

  • To investigate the physiological effects of an oral glucose load on serum testosterone levels in men.
  • To assess how varying degrees of glucose tolerance affect the testosterone response to glucose ingestion.

Main Methods:

  • A cross-sectional study involving 74 men aged 19-74 years.
  • Participants underwent a 75-g oral glucose tolerance test with blood sampling at multiple time points (0-120 min).
  • Serum levels of glucose, insulin, total and free testosterone, LH, SHBG, leptin, and cortisol were measured.

Main Results:

  • Glucose ingestion caused a significant 25% decrease in mean serum testosterone levels.
  • Testosterone levels remained suppressed for 120 minutes post-glucose load.
  • The testosterone reduction was consistent across normal, impaired, and diabetic glucose tolerance groups and did not correlate with BMI.

Conclusions:

  • Oral glucose load significantly reduces total and free testosterone in men, irrespective of their glucose tolerance.
  • The observed decrease in testosterone suggests a direct testicular defect, potentially with central regulatory involvement.
  • Low nonfasting testosterone levels warrant re-evaluation under fasting conditions.